FORT LEONARD WOOD, Mo. (AP) — An Army staff sergeant based in Missouri is accused of sexually assaulting several female soldiers since 2011.

The Washington Post reports ( ) that Staff Sgt. Angel M. Sanchez appeared at a pretrial hearing at Fort Leonard Wood on Wednesday and could face a court-martial later this year.

Military prosecutors allege that Sanchez used his position as a drill sergeant on the Army post to threaten some of the women he's accused of assaulting.

Tiffany Wood, a Fort Leonard Wood spokeswoman, says Sanchez is accused of sexually assaulting four women and assaulting eight others by touching them inappropriately.

Several of the women testified at Wednesday's hearing. Sanchez's lawyer, Ernesto Gapasin, told the paper "there are a lot of issues with the credibility of the witnesses and the government's case."